diff --git a/podman_compose.py b/podman_compose.py
index b3ac14f..3a0f09c 100755
--- a/podman_compose.py
+++ b/podman_compose.py
@@ -1278,6 +1278,8 @@ def compose_up_parse(parser):
         help="Don't start the services after creating them.")
     parser.add_argument("--build", action='store_true',
         help="Build images before starting containers.")
+    parser.add_argument("--build-arg", metavar="key=val", action="append", default=[],
+        help="Set build-time variables for services.")
     parser.add_argument("--abort-on-container-exit", action='store_true',
         help="Stops all containers if any container was stopped. Incompatible with -d.")
     parser.add_argument("-t", "--timeout", type=float, default=10,